With all due respect, your choice of language (i.e., “hoarding”) shows what appears to be animosity toward those who have managed to acquire wealth. That’s not a good starting point for a discussion on a workable solution to the extreme inequality that resulted from how our current system is set up.
To do that, one has to start from agreeing on ethics and principles, looking at what is constitutionally workable, and then debating for your point of view without animus toward who you see as the source of funds to do what you want done. Such a solution also needs to be sustainable for the very long term.
Another, more tangible, problem with your position as stated is that the $1.3T gap is an income gap, which would recur each year unless a solution was found that increased the income of those who are currently struggling. The 3.25% in wealth tax you cite would thus also need to be annual.
The income on those trillions of dollars in assets is already taxed. Adding an annual tax on the underlying assets that produce that income is nothing less than a creeping form of nationalization of private wealth and redistribution of that wealth to the poor.
You might see nothing wrong with that, but what do you do after several decades, when that wealth that you’ve been sucking dry runs out? Do you then decide that the threshold for the wealth tax should be moved lower, so you can access a wider tax base? What happens when that wider base is sucked dry? Rinse and repeat? What happens once you’ve rinsed and repeated so many times that all wealth is abolished and everyone is struggling equally?